Teachers may seem like a gloomy bunch of boring grown-ups sometimes, but they have their weaknesses. They may not find slime funny but, did you know, for example, you can make a gym teacher laugh by showing them a video of an animal falling over? They're suckers for animal fails!
The key to a math teacher's funny bone, however, is a harder equation to hack! And science teachers prank using the LAWS OF THE UNIVERSE - so best get on their good side!
Make sure you don't ask an English teacher for a joke - you'll be older than them by the time it gets to the punchline!